Physician contribution to a cesarean delivery risk model

Objective: The purpose of this study was to assess the contribution of physician management to the probability of cesarean delivery. Study Design: A prospective cohort study was performed of all live births who weighed ≥500 g for a 2-year period (1999-2000) at a large metropolitan hospital (n = 10,027 births). Factors that were associated significantly with cesarean delivery at one time excluded cases in which cesarean delivery was a necessary or probable outcome. In the planned vaginal delivery sample (n = 7940 births), a risk-adjusted logistic regression model was used to assess the prediction of cesarean delivery. To test for the effect of physician-management physician, we used the subset of physicians with ≥45 deliveries in the 2-year time period (n = 6563 deliveries). Results: When physician-management physician data were added to the use of forward stepwise regression, entry order was abnormal position, nulliparity, birth weight of >4000 g, and physician. The modelʹs predictive ability improved from 43.8% to 50.2%. Conclusion: Physician management adds a significant independent effect to the cesarean delivery risk model. (Am J Obstet Gynecol 2003;188:1579-87.)